linux/mm/damon
Baolin Wang be2d575638 mm: change to return bool for folio_isolate_lru()
Patch series "Change the return value for page isolation functions", v3.

Now the page isolation functions did not return a boolean to indicate
success or not, instead it will return a negative error when failed
to isolate a page. So below code used in most places seem a boolean
success/failure thing, which can confuse people whether the isolation
is successful.

if (folio_isolate_lru(folio))
        continue;

Moreover the page isolation functions only return 0 or -EBUSY, and
most users did not care about the negative error except for few users,
thus we can convert all page isolation functions to return a boolean
value, which can remove the confusion to make code more clear.

No functional changes intended in this patch series.


This patch (of 4):

Now the folio_isolate_lru() did not return a boolean value to indicate
isolation success or not, however below code checking the return value can
make people think that it was a boolean success/failure thing, which makes
people easy to make mistakes (see the fix patch[1]).

if (folio_isolate_lru(folio))
	continue;

Thus it's better to check the negative error value expilictly returned by
folio_isolate_lru(), which makes code more clear per Linus's
suggestion[2].  Moreover Matthew suggested we can convert the isolation
functions to return a boolean[3], since most users did not care about the
negative error value, and can also remove the confusing of checking return
value.

So this patch converts the folio_isolate_lru() to return a boolean value,
which means return 'true' to indicate the folio isolation is successful,
and 'false' means a failure to isolation.  Meanwhile changing all users'
logic of checking the isolation state.

No functional changes intended.

[1] https://lore.kernel.org/all/20230131063206.28820-1-Kuan-Ying.Lee@mediatek.com/T/#u
[2] https://lore.kernel.org/all/CAHk-=wiBrY+O-4=2mrbVyxR+hOqfdJ=Do6xoucfJ9_5az01L4Q@mail.gmail.com/
[3] https://lore.kernel.org/all/Y+sTFqwMNAjDvxw3@casper.infradead.org/

Link: https://lkml.kernel.org/r/cover.1676424378.git.baolin.wang@linux.alibaba.com
Link: https://lkml.kernel.org/r/8a4e3679ed4196168efadf7ea36c038f2f7d5aa9.1676424378.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-20 12:46:17 -08:00
..
core-test.h mm/damon/core-test: add a test for damon_update_monitoring_results() 2023-02-02 22:33:26 -08:00
core.c mm/damon/core: update monitoring results for new monitoring attributes 2023-02-02 22:33:26 -08:00
dbgfs-test.h mm/damon/dbgfs-test: fix is_target_id() change 2022-03-22 15:57:12 -07:00
dbgfs.c mm/damon/dbgfs: print DAMON debugfs interface deprecation message 2023-02-13 15:54:33 -08:00
Kconfig mm/damon/Kconfig: add DAMON debugfs interface deprecation notice 2023-02-13 15:54:32 -08:00
lru_sort.c mm/damon: use kstrtobool() instead of strtobool() 2022-11-30 15:58:45 -08:00
Makefile mm/damon/modules: deduplicate init steps for DAMON context setup 2022-11-30 15:01:26 -08:00
modules-common.c mm/damon/modules: deduplicate init steps for DAMON context setup 2022-11-30 15:01:26 -08:00
modules-common.h mm/damon/modules: deduplicate init steps for DAMON context setup 2022-11-30 15:01:26 -08:00
ops-common.c mm/damon: convert damon_ptep/pmdp_mkold() to use a folio 2023-01-18 17:12:52 -08:00
ops-common.h mm/damon: remove unneeded damon_get_page() 2023-01-18 17:12:53 -08:00
paddr.c mm: change to return bool for folio_isolate_lru() 2023-02-20 12:46:17 -08:00
reclaim.c mm/damon/reclaim: add a parameter called skip_anon for avoiding anonymous pages reclamation 2023-01-18 17:12:43 -08:00
sysfs-common.c mm/damon/sysfs: make kobj_type structures constant 2023-02-09 16:51:45 -08:00
sysfs-common.h mm/damon/sysfs: make kobj_type structures constant 2023-02-09 16:51:45 -08:00
sysfs-schemes.c mm/damon/sysfs: make kobj_type structures constant 2023-02-09 16:51:45 -08:00
sysfs.c mm/damon/sysfs: make kobj_type structures constant 2023-02-09 16:51:45 -08:00
vaddr-test.h mm/damon/vaddr-test.h: stop using vma_mas_store() for maple tree store 2023-02-09 16:51:35 -08:00
vaddr.c mm/damon/vaddr: record appropriate folio size when the access is not found 2023-01-18 17:12:58 -08:00